Making contributing.rst more beginner friendly
Adding info about mne-scripts
Addressing @agramfort's comments and adding more stuff
Addressing @dengemann and @agramfort's comments
Minor fix
Minor fix #2
Making ipython in all small caps
Misc changes

- Making symbolic link step more generic.
- Addressing comments by @rgoj.
Small fixes suggested by @rgoj
Merge pull request #688 from mainakjas/contributing

WIP: Making contributing.rst more beginner friendly